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Alodine 1201 versus Alodine 1200S
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Customer called out Alodine 1201 as a replacement for alodine 1200S. What is the difference between these products?
Best Regards, Menno Velthuijs.
Menno Velthuijs- Nieuw Vennep, Holland, Europe
-Alodine 1201 is a ready-to-use chromate conversion chemical; that is, for its original purpose there are no make-up or control parameters to be concerned about. In terms of U.S. military specifications, which many aircraft companies use as a guide, it is qualified under the Qualified Products List Mil-DTL-81706 [link is to spec at TechStreet] as a brush-on only. It was created primarily for touch-up and repair of scratched surfaces which had been previously anodized or chromated. If not tied into a specification such as the above, it can be diluted 1 part: 2 parts water to make an immersion bath for chromating new parts. As a bath it can be controlled like Alodine 1200S.
Alodine 1200S is a powder, chromate conversion chemical which must be dissolved in water to make a bath, which is then used to chromate aluminum. Under the QPL it is qualified for immersion, spray, or brush-on coatings. In terms of processing aircraft parts, AL 1200S has been the benchmark of the industry for over 40 years. Alodine 1201 is similar to a 20 gram per liter solution of Alodine 1200S. The AL 1200S can be used anywhere AL 1201 is used, but for large amounts of touch-up work or if handling of a liquid is preferred, AL 1201 is more convenient.
We are not aware of immersion baths of Alodine 1201 being used on a long-term basis, and if the reason for using it is strictly to handle liquids, we have another liquid product on the above QPL, Alodine 1600, which was designed for long- term use in immersion or spray baths.
Phil Johnson
Madison Heights, Michigan
May 13, 2010
Will this Alodine 1200 or 1201 color pot metal, such as a carburetor?
Burke Young- Farmersville, Texas
May 17, 2010Hi, Burke. Chromate conversion chemicals do color both zinc and aluminum, although corrosion resistance rather than tinting is their purpose. The particular proprietaries that were mentioned are designed for treating aluminum surfaces, not zinc diecastings, but they probably will turn zinc somewhat yellow, even if not actually designed for the purpose. It's a bit like asking if you can use yellow house paint on your car because you prefer yellow to its present color, though; you'd be better off picking a chromate conversion chemistry that is designed for zinc diecastings.
But please note that these solutions are based on chromic acid (toxic and carcinogenic "hexavalent chromium"). To use toxic materials for purposes for which they are not intended probably isn't a good idea.
Regards,
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
April 19, 2011
Phil,
Does this agent change the colour or finish of aluminium too? I would like to use it as a pre-coat on alloy rims before putting a clear finish on them.
- Louisville, Kentucky, USA
April 20, 2011
Hello, Hilton. Yes, but again, it's purpose is corrosion resistance/pretreatment rather than coloration and you may not be happy with its uneven appearance.
Regards,
Ted Mooney, P.E.
finishing.com
Brick, New Jersey
May 29, 2011
Thanks for the response, I apologize for asking a question that was already answered above if only I'd read carefully through your description.
My main concern is paint adhesion. I've decided to go ahead and just paint them vs just a clear finish and I've heard that it's hard to get paint to adhere to Aluminum surfaces. Any suggestions would be helpful.
- Louisville, Kentucky, USA
May 2011
Hi again.
If you plan to use paint rather than having the aluminum look show through a clear coat, then the Alodine conversion coating idea is a very good pretreatment to help with adhesion to aluminum surfaces. Good luck.
Regards,
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |